Electrical entrance plug



Jan. 28, 1936. R. H. MONEY ELECTRICAL ENTRANCE PLUG Filed Sept. 18, 1935 INVENTOR. Benn/v0 HMQNEX BY q- ATTORNEYS.

Patented Jan. 28, 1936 ELECTRICAL ENTRANCE PLUG Roland H. Money, Cincinnati, Ohio, assignor to The Crosley Radio Corporation, Cincinnati, Ohio, a corporation of Ohio Application September 18, 1935, Serial No. 41,106

2 Claims. (01. 173--311) My invention relates to entrance plugs for electrical conductors or an electrical conductor, which provements consist in providing for a tight compressed fit of the gasket without resetting it after treatment of the casing into which it is introduced.

Such entrance plugs are used, for example, in sealed casings containing the compressor and motor for a refrigeration machine. After such casings are built it is necessary to bake them out, and entrance plugs using rubber compressible gasket means, get out of adjustment due to the action of heat on the parts. Also heat and cold on the units'effects changes in the metal parts, which changes the compression on the gasket and may lead to its leakage. Such has been my experience with these devices.

According to my invention I provide a heavy spring as part of the element which presses down on the gasket, which spring takes up any looseness of parts resulting from changed heat conditions on the rest of the plug, or from change in the rubber itself from time to time.

I have illustrated in the appended drawing an illustration of my invention and in the claims that follow will set forth the novelty inherent therein.

In the drawing, the figure is a longitudinal section taken through the plug.

I have illustrated at la casing through which the plug is to pass. The metallic terminal post or conductor is shown at 2. Surrounding the portion thereof which enters the casing is a tubular element 3 of insulation material, e. g. Bakelite, with a flange 4 which engages the interior of the casing and holds the tubular element against withdrawal. The hole in the casing fits the tubular .element closely except at the outer portion 5 thereof which is of larger bore. This Bakelite tube is gas tight to the terminal post and preferably molded thereon.

Into the larger bore portion is set a compressible rubber ring or gasket 6. Set over the terminal post is a sleeve 1, of insulation material having a flange which fits down in the space between the tubular member and the casing, where the rubber gasket has been inserted and by pressing down on this sleeve the rubber will be compressed about the tubular element and against the walls of the casing, sealing it tightly against influx or efliux of gas or air.

In order to force the sleeve down to scaling position, the upper end of the terminal post is 5 threaded and fitted with a nut 8. Two spring cups 9, 9,are placed over the terminal post with a heavy spring l0 between them, and the nut presses upon this assembly, and through it applies resilient pressure to the rubber gasket mem- 10 her.

The electrical conductor l l, is set over the post above the nut and a knurled binding post cap applied to maintain the conductor in place.

As so constructed, it is evident that the rub- 15 her gasket is held tightly in sealing position by the force applied through the heavy spring, and that this heavy spring will take up any loss in such compression as is set up, without readjustment of the nut. 20

Having thus described my invention, what I regard as the novelty inherent therein, and in equivalents thereof, and desire to secure by Letters Patent is:-

1. In an electrical terminal plug for the pur- 25 pose described the combination of a non-conductive tube, a terminal element passing through the same, a rubber gasket surrounding said nonconductive tube, and adapted to seat in an annular space about said tube, a non-conductive 30.

sleeve on the terminal member and adapted also to enter said annular space, and means for pressing said sleeve into said annular space compris- 'ing a spring, and a nut pressing upon said spring, and threaded to the terminal member.

2. In an electrical terminal plug for the purpose described, a cylindrical terminal post threaded at its outer end to receive a nut, and having mounted in sealing relation therewith a non-conductive tube having a flange at its outer end, a 40 rubber gasket arranged to fit the outsideof said tube, a sleeve on the terminal post having a flange also arranged to fit the outside of the tube and arranged to be pushed along the tube to compress the gasket, a pair of spring cups with a heavy spring between them arrangedover the terminal post, and a nut on the end of the terminal post engaging the outer one of the spring cups, as and for the purpose described.

ROLAND H. MONEY. 

